Coupling for electric conduits.



No. 657,732. Patented Sept. ll, I900.

E. S. FRANCIS.

COUPLING FOR ELECTRIC CONDUITS.

(Application filed July 8, 1900,)

(No Model.)

isiillllllllilillh UNITED? STATES PATENT OFFICE.

EDWARD s. FRANCIS, or HARTFORD, 'coNNncTIcu'r.

COUPLING FOR ELECTRIC CONDUITS.

ZEPECEFICATION forming part of- Letters Patent No. 657,732, datedSeptember 11, 1900.

Application filed July 6, 1900.

To all whom it; ma concern:

Be it known that I, EDWARD S. FRANCIS, a cil izen of the United States,and a resident of Hartford, in the county of Hartford and State ofConnecticut, have invented certain new and useful Improvements inCouplings for Electric Conduits, of which the following is aspecification.

My invention relates to the class of devices used for connectingelectric conduits with a connection-box; and the object of myinventionis to provide a device of this class that shall be simple, comparativelysmall, and compact for use in connecting or coupling a flexible conduitof peculiar construction to a connection-box.

The preferred form of device embodying my invention is shown in theaccompanying drawings, wherein- Figure 1 is a View in side elevation ofthe coupling and of aconduit and in section of one side of aconnection-box. Fig. 2 is a View, on enlarged scale, in horizontalsection, through the coupling and the thimble. Fig. 3 is a view in endelevation of the coupling, showing the sections separated.

In the accompanying drawings the lettera denotes a connection box ofordinary construction made usually of wrought metal,with a cover I)secured to the box, as by means of screws 0, and having through thewalls of the box openings d, through which a wire or I group of wires 6may enter the box from a conduitf.

Prior forms of coupling devices for conduits have consisted of acylindrical piece screwthreaded to receive a thread on the end of atubular conduitand also to receive the threaded shank g of the tubularthimble g, the wall of'the box at the edge of the opening being clampedbetween the end of the coupling and the flange on the nipple g. One formof flexible coupling in more or less extended use is made of metal, withan outer layer formed of a continuous strip wound spirally about theinner layers, the edges of the strip being quite close to each other.Such a flexible conduit is shown atf, and its outer surface presentspractically a coarse thread rounded as to its surface. This form ofconduit has on account of its peculiar characteristics both ofconstruction and form been a difficult one berial No. 22,736. kllomodel.)

to unite to a connection-box with any known form of coupling, and priorto my invention the devices for this purpose have been crude andbungling. My improved coupling h is made in two sections h 7L2 and istubular in form, the line of division between the sections being in aplane about central lengthwise of the coupling until near one end, whenthe plane of division turns at an angle, and preferably at a rightangle,to the lengthwise plane of division. This coupling has a solidportion near one end forming a complete circle or short tube, while theremainder of the coupling is divided, so that the part It may beseparated from the body of the coupling. The part 7L3 is threaded toreceive the threaded shank g of the nipple g, and the remainder of thecoupling is formed on its inner surface to closely fit upon the outersurface of the flexible coupling.

The two sections of the coupling are united by means of bolts or screws1., which extend through registering projections from the sides of thetwo sections. The bolts riextend through the projections on the one partinto threaded sockets in the registering projections on the othersection of the coupling, and by this means the two parts are clampedfirmly together upon the end of the conduit. The nipple is used forfastening the coupling to the wall of the connection-box, which is, asstated, clamped between the end of the coupling and the shoulder formedby the flange on the nipple, the latter being shaped to receive a wrenchor like means for turning it.

My improved coupling is of comparativelysimple construction and forms apositive and compact means for securing the end of the flexible conduitto the connection-box.

It is obvious that the invention is not limited to the precise detailsof construction illustrated and described herein; but changes in suchdetails are contemplated as within the scope of my invention.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. In a coupling for connection-boxes, in combination, a main sectiontubular in form and threaded on the innersurface at one end and havingaremovable section less in length than the coupling and partible on aboutthe central plane lengthwise of the coupling, and

at one end having its inner walls threaded, :L complementary removablesection filming the main section, means for securing, the sectionstogether, a nipple having a shoulder and threaded to fit the tubularopenin in the main section of the coupling, and :L flexible conduithaving its outer-Well formed of El series of spirallyerranged separatebands.

EDWARD S. FRANCIS.

Witnesses:

ARTHUR B. JENKINS, ERMA P. COFFRIN.

